Any woman who’s used hormonal contraception will likely tell you that, while the pill is great for helping us stay in control of our reproductive choices (thank you, birth control!), it also sometimes makes us feel like crap. And now, a new randomized study has confirmed just that: The most common type of combined hormonal birth-control pill has been found to negatively impact a woman’s quality of life.

Scientists from the Karolinska Institutet in Sweden gave 340 healthy women between the ages of 18 and 35 either placebos or contraceptive pills containing ethinylestradiol and levonorgestrel over the course of three months. Published in the journal Fertility and Sterility, the study found that women who took the combination pills reported overall reduced feelings of well-being — from a lower quality of life to negative impacts on her mood, self-control, and energy. But despite the negative findings, the scientists noted that the hormonal pill didn’t appear to increase the study participants’ risk of depression.

The scientists noted in a statement that, despite the fact that an estimated 100 million women around the world use contraceptive pills, the medical community still knows “surprisingly little” about the pill’s effect on women’s health. As a result, there’s a great need for studies like this one, which actually compares the pill’s effect with placebos. The scientists added that because the perceived changes in the study were relatively small, the findings should be interpreted cautiously. However, they also noted that the pill’s negative impact on individual women could be of clinical importance.

“This might in some cases be a contributing cause of low compliance and irregular use of contraceptive pills,” study co-author Dr. Niklas Zethraeus said in a statement. “This possible degradation of quality of life should be paid attention to and taken into account in conjunction with prescribing of contraceptive pills and when choosing a method of contraception.”